The radio broadcast (with pictures, oddly enough) can be found
on
the BBC website (See the
26
August 2002 entry.)
You'll need RealAudio software to listen to it on the web.
The Tongues story is in two segments, one starting about half-way into
the show (at about the 17 minute mark), the other is "expert"
commentary starting at about minute 25. (In between the two is a story
about a Hindi synthesizer, also made with "stuff that has come out of
Carnegie Mellon", i.e.,
Festival.)